The present invention relates to an apparatus for selectively positioning an upper roller of a drafting apparatus of a textile machine in selected operating positions.
The drafting apparatus of textile machine drafts roving or other textile material from a supply of such material. The drafting apparatus typically includes three associated pairs of rollers, each roller pair having an upper roller and a lower roller and with the upper rollers mounted on a carrier member generally pivotally mounted at one end on a pivot shaft for pivoting between an operating position in which the upper rollers are cooperatively disposed with respect to their associated lower rollers to form nips therebetween for the feed of the textile material through the nips and a non-operating position in which the upper rollers are supported at a spacing upwardly from their respective associated lower rollers.
To releasably maintain the carrier member in its operating position, in which the associated pairs of upper and lower rollers are cooperatively disposed for the feed of roving therethrough, the drafting apparatus typically also includes a force-applying member mounted at one end to the carrier member and extending over the top of the carrier member to a free end position which contacts the carrier member to apply a downward roller nip pressure. The force-applying member extends generally centrally laterally over the top of the carrier member.
Each upper roller is rotatably supported on a bracket assembly which is adjustably mounted to the carrier member. The bracket assembly is typically adjustably fixedly secured to the carrier member by a vertically extending attaching stud adjustably movable along a slot on the top of the carrier member and having a top end extending through and above the top of the carrier member for releasable securement for securement thereto. Accordingly, the bracket assembly can be selectively released from its fixed position on the carrier member to allow adjustable positioning of the associated upper roller supported thereon by selectively loosening the attaching stud for movement along the slot in the carrier member, which typically extends in the direction of the feed of the roving. Once the bracket assembly has been repositioned to a new location, the attaching stud is again engaged to fixedly secure the bracket assembly to the carrier member to fix the upper roller in its selected position relative to the carrier member.
The slots along which the attaching studs are movable are located generally along the longitudinal center line of the carrier member. Accordingly, as can be understood, the force-applying member typically extends directly over the slots in superposed relation. To gain access to the top ends of the attaching studs for adjusting the bracket assemblies, it is therefore generally necessary to displace the force-applying member from its operating position in which it urges the carrier member downwardly to bring the upper and lower rollers into feeding engagement with one another.
Accordingly, the need exists for a textile drafting device which permits relatively quick and simple access to and adjustment of the upper roller bracket assemblies for adjusting the position of the upper rollers.